Would you use MR. Heater for temp heat?

[witzgall]

Hi all;

We are headed down to the boat this weekend, and the nighttime temps are predicted to be a bit chilly - 24F on SUnday night. We only have a ceramic heater right now, and I would love to keep the cabin toasty.

Home Depot/Lowes has the Portable Mr. Heaters for sale - the documentation states that they are safe for indoor use:

http://www.mrheater.com/upload/newsl..._eng_rev_c.pdf

Would you use one for temp heat on your boat, or is this stupid? I was thinking of putting it in the bow of the boast, with the external tank adapter hose going out the forward hatch to the tank on deck. This would ensure some ventilation - our top hatch board is vented too. IS that enough? Does carbon monoxide rise or fall?

Chris

[AnchorageGuy]

Bad idea to use a propane, kerosene or other type of fuel fired heater in an enclosed boat period. If you have enough ventilation to eliminate carbon monoxide you are going to loose all of your heat. Carbon Monoxide accumulates and will kill you, that is what you need to know. Can you use it, yes. Should you use it, no.

[David M]

There are heaters that use diesel that are specifically designed for heating boats. Espar makes some. If you are going to use one of those heaters or any sort of heater whose fuel comes from the burning of carbon based molecules, then you definitely want to put a few carbon monoxide sensors around the boat. You should have some CO detectors around your boat anyways if you burn anything onboard.

Espar - Marine

[witzgall]

Yep, I know about the Espar heaters, and that is the type I would like to install at a later date - but that is not going to happen for this weekend!

Chuck - Your response is the usual safety first one. I am not saying that is bad, but I have to wonder - the company that makes these sells them to folks who use them in trailers, boats, cabins, etc. They have a Oxygen depletion sensor. I was also thinking of putting a CO detector onboard anyways, and if so have I mitigated the danger? OR does this fall into the "those sensors have failed in the past, not worth the risk" category.

Having said that, I think I will end up buying another ceramic heater, and just running them both on low.

Chirs

Chris

[projectfiji]

I use Mr. Heaters for all kinds of odds and ends heating tasks. We use them in deer blinds, ice shanties, etc. I've got a buddy that uses a Mr. Heater to heat his cargo van (that he sleeps in, he's an expediter). You mileage may vary.

If you go with one, make sure you pick up a CO detector and try to keep the area ventillated as best as possible (Cargo van guy keeps his windows cracked even in the dead of the winter.

PF

[David M]

If you are going to do that, then get the CO sensors...at least two. O2 depletion sensors are not the same thing. You can have plenty of O2 and still die of CO poisoning. Personally, I would not take that chance.

[witzgall]

All;

Thanks for the good advice. Out of curiosity, I called the manuf. of the heaters. I asked it I would kill myself by using one of these heaters on a sailboat. I figured that question would cut through all of the bull.

The guy, or course, said that if that were the case, they would not sell them. He said they were safe, did not put out allot of CO (how is that possible) and that if I wanted, I could crack a "window" 1/4 inch.

Chris

[rodney_k]

I've used one aboard occasionally. No problems other than a little moisture put into the air from the combustion. I will not sleep with it running however. I crack the hatch in the compartment the heater is in... Lewmar hatches in the "ventilation" position.

[Ron_Fran]

I would be worried more about propane than CO. Since propane is heavier than air, a leak would cause it to collect in your bilge.

We use an electric heater, the kind that looks like a radiator. It takes keeps our boat pretty warm.

[easterly]

I have no issues using a propane heater in my boat, as long as it has a oxygen depletion sensor. I have a CO detector/alarm and propane detector/alarm.

[cal40john]

Originally Posted by David M

If you are going to do that, then get the CO sensors...at least two. O2 depletion sensors are not the same thing. You can have plenty of O2 and still die of CO poisoning. Personally, I would not take that chance.

I'd still get another CO detector in any event but;

It seemed to me that it would be much more difficult, though I'm sure somewhere somebody has managed to do it, to seal a boat/RV whatever well enough to die of a lack of oxygen. It seems much more likely to die of CO. So it seemed strange to me to put oxygen sensors instead of CO detectors on heaters since it only takes 10s of ppm of CO to kill you. Propane is supposed to burn pretty cleanly to water and carbon dioxide if it has the right air/fuel mixture, but will produce CO if the air/fuel is off. I did a little looking and found this website which makes much more sense to me.

http://www.irvingtongas.com/pdf/Rinn...tionSensor.pdf

(bottom of page)

Basically the oxygen sensor is an indirect way of measuring CO. When the oxygen gets low enough, about equivalent to being at an elevation of 4000 feet if I did my math right, the air/fuel mixture is off far enough to change where the pilot flame burns and turns off the heater. This presumeably is where the air/fuel mix is far enough off to produce enough CO to worry about as well.

I found one brand of heater does not work above 7000 ft and another doesn't work above 5000 ft, so maybe my calculation is off, or the above website is conservative. So these heaters shut off long before you're in any danger of oxygen deprivation. I would think that you would die of CO poisoning or CO2 asphixiation long before O2 problems with any sort of combustion process.

Next thing I'd like to find out is how likely are you to get enough CO2 in the boat to worry about.

Carbon Dioxide compared to Carbon Monoxide

If it is obvious to everyone but me that the ODS is an indirect CO detector, then I apologize in advance for being pedantic.

John

[SeaKing]

I have one of the mr heater "lil' buddy's that i use to warm the salon when I go down to boat to do any cold weather work. I am not sleeping . I set the heater on one side of the salon and on the other side open a top/overhead lewmar hatch"20"x20" about 1 inch for top ventilation and usually have the main sliding glass door open about an inch too.

For this weekend how about use your Mr heater with adaquate ventilation to keep cozy while awake and when you sleep try an electric blanket(nice and cozy warm) and the ceramic heater to keep the chill down. Then when awake open the ventilation and fire up the Mr.Heater.

[Bloodhound]

Burning propane or diesel for heating a confined space doesn't necessarily produce CO but it will if enough excess air isn't used. And as a user, you probably have little say about how the burner is set up. However, the amount produced (and so the CO concentration in the atmosphere inside the boat) is almost assuredly small. The qualifier is that every boat with an inboard engine should have a CO alarm anyway, and it should be tested frequently. If you do those things you'll be as safe as you possibly can be, short of not burning anything at all and risking hypothermia.

[stevensc]

I bought one last week and have been using it during the day to keep the cabin or enclosed flying bridge of my trawler warm while cruising. It works well and as previously mentioned does have a low oxygen shut off. We keep a window cracked open a bit and only use it while awake.
We are happy with it.
Steve

[Zach]

I've used one to take the chill off before bed on a little trailer sailer...

Does the job! I didn't sleep with it on...